According to the CBI, cases have been registered against Lalu Prasad, his wife Rabri Devi and their son Tejashwi, who is the deputy chief minister of Bihar.

RJD chief Lalu Prasad addresses a press conference with his son and Bihar deputy CM Tejashwi Yadav at his residence in Patna.(PTI)

Cracks in Bihar’s ruling alliance appeared to deepen on Monday over differences on how to combat corruption charges against deputy chief minister Tejashwi Yadav, even as senior coalition partner Rashtriya Janata Dal backed him and ruled out his resignation.

The RJD’s 80 MLAs in Patna unanimously decided to back Tejashwi and his father, party chief Lalu Prasad, who are facing charges in an alleged land-for-hotels scandal that saw the Central Bureau of Investigation raiding their homes and other properties last week.

“The meeting praised the work of Tejashwi… there is no instability in the coalition government. The BJP is trying to destabilise it,” said senior RJD leader and state finance minister Abdul Bari Siddiqui, blaming the BJP for CBI raids on Lalu’s residence last week.

The storm of corruption allegations – and fierce demand by the BJP for Tejashwi’s resignation -- has put the spotlight on chief minister Nitish, who has had several run-ins with the RJD since coming to power two years ago.

The raids on Lalu and his family came at a time when his ties with Nitish are fraying over the latter’s drift towards rival Bharatiya Janata Party and its presidential candidate Ram Nath Kovind.

Throughout the day, Nitish was huddled with top party leaders and senior ministers, and a JD(U) meeting – comprising all state executives -- scheduled on Tuesday is expected to announce the party’s stand on the issue.

“This clearly signals the current political scenario will be discussed at the meeting. I think, by Tuesday evening the scenario will be clearer,” said a JD?(U) leader familiar with the developments.

JD (U) sources admitted the 18-month old alliance was passing through a turbulent phase.

“The CM is definitely caught between his zero-tolerance against corruption policy, on the one hand, (and) fear of the alliance breaking midway,” said a senior party leader.

Bihar BJP president Nityanand Rai told TV news channels on Monday said the party will back Nitish’s government from outside if the RJD and Congress withdrew from the ruling alliance.

Although Nitish’s Janata Dal (United) has remained silent on Tejashwi’s resignation, it has backed Lalu on the raids and said the BJP won’t succeed in breaking the Grand Alliance. The chief minister himself decided to skip an Opposition meet to fix the vice-presidential candidate on Tuesday, and decided to send senior leader Sharad Yadav instead – a repeat of the move before a similar Opposition meet to decide its presidential candidate last month.

A possible meeting between Nitish and Congress vice-president Rahul Gandhi on Monday didn’t take place either. The Congress is said to be tilting towards Lalu.

Nitish is said to be uncomfortable with the growing influence of Lalu’s family on the coalition and the shadow the graft charges have cast on his brand of politics, built on a promise of clean and corruption-free governance.

RJD leaders downplayed reports of the rift and former MP Jagadanand Singh said Nitish had spoken to Lalu on Sunday night but didn’t elaborate on the contents of the conversation.

The CBI registered a case last week against Lalu Prasad, his wife Rabri Devi, son Tejashwi and other officials for allegedly illegally awarding hotel maintenance contracts to private firms when the RJD chief was the railway minister.

Nitish – who has 71 MLAs – joined hands with Lalu before the 2015 assembly polls to stave off a BJP victory. But the Grand Alliance’s sweeping victory was followed by months of public rift between senior leaders of both parties, though Lalu and Nitish have never come out in public with any differences.